1. FIELD OF THE INVENTION:
This invention relates to coated carbon fiber reinforced polymer composites and to the coated carbon fiber. More particularly, this invention relates to organic polymer matrix composites reinforced with carbon fibers which are surface treated with vapor deposited polybutadiyne.
2. DESCRIPTION OF THE PRIOR ART:
The adhesive bond between a carbon fiber and matrix resin is critical to the performance of composite materials. As stated by D. W. McKee and V. J. Mimault, in the chapter, "Surface Properties of Carbon Fibers", Chemistry and Physics of Carbon, Eds. P. L. Walker, Jr. and P. A. Thrower, Marcel Dekker, Inc., New York, pp 190-220, (1973) and H. Ishida and J L. Koenig, Eds.,in Composite Interfaces, Elsevier Science Publishing Co., Inc., New York, (1986) improvement and understanding of the bonding of this interface region has been and continues to be an important research objective. Surface treatment of the carbon fiber has a pronounced effect on the quality of the adhesive bond. As shown in the McKee reference referred to above, the treatments involve a variety of chemical etching and coating deposition techniques. The effects by which these treatments promote adhesion are believed to involve a complicated mixed contribution from surface roughness, improved fiber wetting and enhanced chemical interaction.
Endou, et al., in U.S. Pat. No. 4,596,741, describes the use of SiC coatings to provide coatings for carbon fibers in carbon fiber reinforced plastic and metal composites. Yee, et al. in U.S. Pat. Nos. 4,208,501 and 4,125,534 suggests that diacetylenic polymers can be formed by vapor depositing particular monomers and subsequently converting them to a polymer. For totally different purposes, Garito, in U.S. Pat. No. 4,581,315 describes forming polymer films by vapor deposition from diacetylinic monomers. Froch, et al., in U.S. Pat. No. 4,321,299, describes a fiber reinforced structure wherein a polymer is formed from vapor deposited monomers.
It is still necessary to provide a carbon fiber coating compatible with both the particular form of carbon fiber and the polymer matrix.